Question: What is a mathematical model that starts with the letter t.
Paraphrase: What is a model of mathematics that begins with letter t.
SPARQL (Wikidata): SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q486902 . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 't')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
Answer: Theoretical gravity, Theoretical gravity, Ten15, Ten15, Trochoidal wave, Trochoidal wave, Traffic model, Traffic model